Minimal content model for element blockquote is "(PCDATA | Heading | Block | List)*".
Minimal content model for div is "(PCDATA | Flow)*".
Text Module declare "Flow" to be equivalent to "Heading | Block | List".
Later declarations in other modules add elements to Flow content set.
For example, List Module adds List content set to Flow content set.
Such declaration of blockquote minimal content model lead to, in my opinion, strange restriction: while using List Module it is impossible to use lists inside blockquote, while possible to use it inside divs which is permitted inside blockquote.
Is it designed feature?